1. Field of the Invention
This invention relates to a novel dispersion of magnetic particles and, more specifically, to a dispersion of magnetic particles suitable for use in the preparation of photographic elements having a transparent magnetic recording layer.
2. Description of the Prior Art
Photographic elements containing transparent magnetic recording layers are described in U.S. Pat. No. 3,782,947 to Krall and U.S. Pat. No. 4,279,945 to Audran et al. These patents teach that dispersions of the magnetic particles are prepared by milling or otherwise dispersing magnetic particles in a composition including a transparent binder for the particles and a solvent for the binder. According to U.S. Pat. No. 4,279,945 the dispersing medium can also contain transparent addenda, for example, plasticizers or lubricants. A problem with such dispersions is that the magnetic particles have a tendency to agglomerate, forming clumps of non-uniform sizes. Such agglomerations of particles can cause light scattering and increase the optical density of the magnetic recording layer rendering it unsuitable for use in photographic elements.